Japan waits on Venus spacecraft
Japan's space agency (Jaxa) is working to establish the status of its Akatsuki mission to Venus.
The spacecraft fired its main engine just before midnight GMT on Monday in a manoeuvre designed to allow the planet's gravity to capture the probe.
Akatsuki then briefly lost contact with Earth as it moved behind the Venus.
Scientists said they would know later on Tuesday whether the operation to insert the satellite into the correct orbit had been successful or not.
Akatsuki was launched to the inner-world by an H-IIA rocket in May. Its goals include finding definitive evidence for lightning and for active volcanoes.
It will not be alone at Venus; the European Space Agency's Venus Express craft arrived at the planet in 2006. The pair are due to conduct joint observations.
Venus is almost identical in size to our planet, and is thought to have a similar composition. But there the resemblance ends.
AKATSUKI ('DAWN') VENUS ORBITER
- Will study atmosphere and surface
- Size: 1.0m by 1.4m by 1.4m
- Mass at lift-off: About 500kg
- 5 cameras; 1 radio experiment
- Designed for 4.5-year life
- Will sit in 300km by 80,000km orbit
The thick Venusian atmosphere is opaque to instruments that operate at visible wavelengths and so the Japanese probe carries five cameras that are sensitive in the infrared and ultraviolet parts of the electromagnetic spectrum.
This instrument suite will enable scientists to investigate the clouds layer by layer.
Infrared sensitivity can also be used to study surface composition. This is how scientists hope to detect active volcanism.
Europe's Venus Express probe recently found lava flows that could have been younger than 250,000 years old.
It has been a busy year in space for Japan.
The major success was the safe return to Earth of the Hayabusa probe which had collected dust grains from the surface of an asteroid.
The same H-IIA rocket that launched Akatsuki also launched the country's Ikaros solar sail - the first practical demonstration of a spacecraft being propelled around the Solar System by the pressure of sunlight alone.
Assuming Monday's manoeuvre worked properly, three more engine burns are planned to refine Akatsuki's orbit before science operations can get under way in earnest.